A web browser may comprise functionality that is configured to access and request resources embedded within a webpage to be rendered by the web browser. However, a content modifier such as a third party add-on of the web browser may be configured to modify, substitute or block one or more particular types of resources associated with the webpage prior to rendering by the web browser. Such content modification functionality may typically utilize a range of techniques to modify the webpage. Typically, these modifications are performed automatically as a background process and without the knowledge or explicit consent of a user of the web browser or a publisher of the web content. Moreover, these modifications may negatively impact the functionality and aesthetics of the content, thereby compromising the integrity of the webpage. In order to prevent content modifiers from affecting the integrity of the webpage, resource identifiers (e.g., URL of resources) of the webpage may be encoded to obfuscate the identity of the resources to prevent the content modifier from targeting certain resources for modification/blocking. However, encoding resource identifiers also obfuscates it from a user that may desire to access the original content identifier (e.g., to identify a source of the content referred by the content identifier).